Add ability to get file/folder properties

[noughtmare]

Is it possible to add a function like:

getProperties :: FilePath -> IO Properties

data Properties = Properties {
  name :: String
  type :: String
  size :: Integer
  etc...
}

Thank you!

[Rufflewind]

• name: Basename of the file?
• type: What do you mean by type of a file? Mind giving some examples?
• size: This is useful. I was not able to find another library that does this portably.
• etc: Would you mind clarifying which properties you are interested in?

[noughtmare]

Sorry, I was being way to vague and general.

For my current project I really only need a function that gets the mime type of a file (i.e. image/jpeg) and a function that checks if a filepath is a directory:

getMIMEType :: FilePath -> IO String
isDirectory :: FilePath -> IO Bool

[Rufflewind]

Since MIME types are not stored as part of the files themselves, there is no accurate way to determine the MIME type without applying a tedious set of heuristic algorithms on the contents of the files. Unfortunately, this means it does not lie within the scope of directory. Consider using the magic library instead.

isDirectory might be a useful addition. Currently, there is doesDirectoryExist, which doesn't quite do the same thing but suffices for many albeit not all purposes.

[Rufflewind]

So I went ahead and implemented the following:

• getFileSize :: FilePath -> IO Integer
• doesPathExist :: FilePath -> IO Bool

I was originally going to implement isDirectory, but I felt that adding doesPathExist is more useful, since it can be used to implement both isDirectory and isFile, while also avoiding naming conflicts with unix.

One could then implement isDirectory like this:

isDirectory :: FilePath -> IO Bool
isDirectory path = do
  exists <- doesPathExist path
  if exists
    then doesDirectoryExist path
    else ioError (mkIOError doesNotExistErrorType "isDirectory" Nothing (Just path))